<HTML><HEAD><TITLE>\/(+Number1, +Number2, -Result)</TITLE>
</HEAD><BODY>[ <A HREF="index.html">Arithmetic</A> | <A HREF="../../index.html">Reference Manual</A> | <A HREF="../../fullindex.html">Alphabetic Index</A> ]
<H1>\/(+Number1, +Number2, -Result)</H1>
Evaluates the bitwise disjunction Number1 \/ Number2 and unifies the
resulting value with Result.


<DL>
<DT><EM>Number1</EM></DT>
<DD>Integer.
</DD>
<DT><EM>Number2</EM></DT>
<DD>Integer.
</DD>
<DT><EM>Result</EM></DT>
<DD>A variable or integer.
</DD>
</DL>
<H2>Description</H2>
   This predicate is used by the ECLiPSe compiler to expand evaluable
   arithmetic expressions.  So the call to \/(Number1, Number2, Result) is
   equivalent to
<PRE>
    Result is Number1 \/ Number2
</PRE>
   which should be preferred for portability.
<P>
   This operation behaves as if operating on an unlimited length two's
   complement representation.
<P>
   In coroutining mode, if Number1 or Number2 are uninstantiated, the call
   to \//3 is delayed until these variables are instantiated.

<P>

<H3>Modes and Determinism</H3><UL>
<LI>\/(+, +, -) is det
</UL>
<H3>Exceptions</H3>
<DL>
<DT><EM>(4) instantiation fault </EM>
<DD>Number1 or Number2 is not instantiated (non-coroutining mode    only).
<DT><EM>(5) type error </EM>
<DD>Number1 or Number2 is a number but not an integer.
<DT><EM>(24) number expected </EM>
<DD>Number1 or Number2 is not of a numeric type.
</DL>
<H2>Examples</H2>
<PRE>
Success:
      \/(11, 7, 15).
      \/(11, -7, Result).     (gives Result = -5)
Fail:
      \/(1, 2, 4).
      \/(6, 2.0, 6.0).
      \/(5, 2, r).
Error:
      \/(A, 2, 6).              (Error 4).
      \/(4 + 2, 2, 6).          (Error 24).



</PRE>
<H2>See Also</H2>
<A HREF="../../kernel/arithmetic/is-2.html">is / 2</A>
</BODY></HTML>
